Ok if I have never said it before I'll say it now ...... you MUST soak your hydrotron in PH balanced water until the water is at the ph needed so it might take a couple times of soaking to get PH down. That being said guess what I didnt do .......... constant PH rise and only thing I can think of is a 50# bag of Hydrotron was added to what I already had and it got rinsed real well but didnt think ahead and didnt have time to soak as clones were going into their buckets